1. Field of the Invention
The present invention relates to a touch panel, and more particularly, to a touch panel with pixels wherein each pixel has light sensing components and pressure sensing components.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 is a diagram illustrating a pixel Pa of a conventional touch panel. As shown in FIG. 1, the pixel Pa comprises a switch SW and a photo sensing component PT. The switch SW can be realized with a Thin Film Transistor (TFT). The light sensing component PT can be realized with a photo transistor or photo diode. One end of the light sensing component PT is coupled to the second end of the switch SW, and the other end of the light sensing component PT is coupled to a bias voltage source Vb. When the light sensing component PT senses light, which means the pixel Pa is not touched, the current I is generated and pulls down the voltage Va to voltage Vb. On the other hand, when the light sensing component does not sense light, which means the pixel Pa is touched, the current I is not generated and the voltage Va keeps at the same level. The control end of the switch SW is coupled to the corresponding gate line of the pixel Pa, and the first end of the switch SW is coupled to the corresponding data reading line of the pixel Pa, whereas the second end of the switch SW is coupled to one end of the light sensing component. The switch SW couples the first end of the switch SW to the second end of the switch SW when receiving the gate driving signal from the corresponding gate line, and thus the corresponding data reading line of the pixel Pa receives the voltage Va. In this way, the conventional touch panel determines if the pixel Pa is touched according to the level of the voltage Va.
However, the drawback of the conventional touch panel is that when there is no ambient light around the conventional touch panel, the light sensing component PT can not sense the variation of light. Hence the conventional touch panel can not determine if the pixel Pa is touched. In this situation, the application of the conventional touch panel is limited.